Automatic fire door



April 24, 1934.

J. A. PAUL AUTOMATIC FIRE noon Filed July 9,. 1932 INVENTOR. 1114136610;

/\/ IlllI/lllllllll I A TTORNEY.

Patented Apr. 24, 1934 UNITED STATES PATENT OFFICE Claims.

This invention relates to an automatic fire door for use in buildingsgenerally, and has to do particularly with a mechanism for closing afire door of the roller curtain type.

Almost without exception fire doors of the roller curtain type arecarried upon a drum or roller above the door opening which is to beclosed in the event of fire in the building. Usually a coiled spring isused as a means for turning the curtain drum to unwind and lower thecurtain. Various arrangements of gears and the like have been employedfor coupling the drum to the spring so that the effort of the spring maybe governed in a manner to provide for a retarded and uniform descent ofthe curtain.

Among the objects of the present invention is the provision of a firedoor closing mechanism adapted to lower a curtain into an opening of anyheight.

A fire door closing mechanism requiring no added parts or additionaladjustment when placed in a doorway requiring a greater or lessercurtain travel.

7 An improved and simplified escapement for controlling the closingmovement of a fireproof curtain.

Improved means for coupling a spring to a drum to rotate the latter sothat a fireproof curtain may be unwrapped therefrom.

These objects, and other desirable objects are obtained through thenovel arrangement, unique combination and improved construction of theparts comprising the present device which is fully set forth in thefollowing description when taken in connection with the accompanyingsingle sheet of drawing hereby made a part of this specification and inwhich:

Figure 1 is an end view of the device taken in end elevation;

Figure 2 is a perspective view of the device taken from ,the above:

Figure 3 is an end view of the deviceillustrating the operatingposition; and

Figure 4 is a horizontal sectional View of the device.

Like reference characters are used to designate similar parts in thedrawing and in the description of the invention hereinafter given.

Reference should be had first to Figures 1 and 2. A mounting bracket isprovided to support the curtain barrel or drum 11 and the primaryoperating gear 14 which, through the gears 28 and 29 in combination witha pull chain gear 30 having a chain 300. thereon, is caused to revolve(by manual movement) to either roll or unroll from the drum a fire proofcurtain (not shown). The drum 11 will usually have the curtain wrappedthereabout so as to unroll when the drum is rotated in a clockwisedirection with reference from the right end of the drum, Figure 1.

The primary gear 14 is loosely keyed to the hub 11a of the barrel 11 topermit a slight rotational movement of the gear on said hub. A shaft 12extends into the barrel 11 and through said hub. The shaft 12 is free torotate within the bearing in the hub 11a and another bearing (not shown)further within the drum 11. To this shaft 12 a conventional escapementratchet gear 17 is rigidly attached by means of a pin 42. A lug (notshown) on the hub ofthe gear 17 loosely meshes a like lug on the gear 15so as to permit a limited rotational movement between the two gears.

One end of a'torsional motive spring 13 is attached to the shaft 12 at12c and thus is connected indirectly to the gears 17 and 15. Theopposite end of the spring 13 and which is not shown may be fixedlyanchored to an immovable shaftor rod which extends inwardly of the drum11 from the end opposite to that shown. Holes 16 are provided in bosses16aprojecting from the gear 15 for the insertion of a lever so that thegearand the shaft 12 may be turned thereby to adjust the tension ofthespring 13. The spring 13 urges the shaft 12 and the gears 15 and 17thereon to rotate in a clockwise direction as viewed from the right endofthe shaft 12. Hereinafter in this description the direction ofrotation of the various gears, shaft and drum will be with. referencefrom such right end unless expressly stated otherwise. 1

A double gear 18 is slidably mounted on a stationary shaft 19 and in theposition shown in Figure 2 only the left gear element is meshed, theconnection being with the gear 15. The shaft 19 is supported by abracket 20 which is'rigidly attached to the mounting bracket 10 in anystandard manner. To this bracket 20 is pivoted at 22 a lever member 21having three congruent legs. The upwardly projecting leg of the lever21, by means of a pin 23 between the two elements of the double gear 18,may slide the gear 18 along the shaft 19. A counter clockwise movementof the lever 21, Figure 2, will through the agency of the pin 23 carrythe gear 18 into common mesh with the two gears 14 and 15 so thatrotation of the latter will cause a like rotation of the former. One armof the lever member 2lhas a hooked end 24 which engagesthe arm 28 tosupport the chain hoist gear housing 25 to keep the gear 28 meshed withthe primary gear 14. v

Supported at the end of a horizontally arranged rod 21a is a weight 40which is provided with an eye 41. The weight 40 is engaged by a cord orwire (not shown) that has an end passed through the eye 41. By means ofthe said cord or wire the weight 40 is supported at an elevationsubstantially equal to the pin 22 whereby the leg of the lever 21 towhich the weight 40 is attached may be maintained in a horizontalposition. If it were not for the means supporting the weight 40, itwould drop to pivot the lever 21 in a counter-clockwise direction,Figure 2 A section of the said cord or wire having an end engaged to theeye 41 for supporting the weight 40, is replaced by one or more fusiblelinks. The links are of an alloy metal of low melting temperature whichhas long since been the subject matter of commercial use.

The housing is pivoted at 27 and is capable of dropping to the positionshown in Figure 3. An arm 34 projecting from the housing 25 carries anescapement lever 35. A conventional pawl 31 ispivotally connected to thehousing 25 by means of a pin 33 and has a projection 32 for engaging theratchet gear 1'7 to prevent the uncoiling of the spring 13.

In order to set the device so that it will operate in case a hightemperature is reached within a building, such as would be caused by afire, the housing 25 is pivoted in the position shown in Figure 1. Thehousing is locked in this position by roating the lever 21 in aclockwise direction, Figure 2, to place the hook 24 beneath the arm 26and supporting the weight 40 by means of the cord or wire containing thefusible link heretofore described. When in this position, the lever 21displaces the double gear 18 to the position shown in Eigure2 so thatthegear 14 which is connected to the hub 11a will be free to rotate thedrum 11. Gear 28, when the housing 25 is rotated in its most clockwisedirection, is meshed with the gear 14 so that the curtain (not shown)may be rolled upon the drum 11 by manipulating the chain 30a which mayhang over the sprocket wheel 30 in the conventional manner.

when a sufllciently high temperature isreached within the building thefusible link above mentioned will melt to allow the weight 40 to dropthereby pivoting the lever 21 to carry the double gear 18 into commonmesh with the gears 14 and 15. Simultaneously, the lock 24 will releasethe arm 26 so that the housing 25 may drop down into the position shownin Figure 3. When the housing 25 is dropped to this position the pawl 32is carried away from the ratchet wheel 17 so that the latter will befree to turn under the impetus of the spring 13. If it were not for thelever escapement 35 which is pivoted at 36 upon the lever 34, the spring13 would cause the shaft 12 and the escapement wheel 17 to rotaterapidly in a clockwise direction. The speed of rotation of the shaft 12and the ratchet wheel 17 is, however, governed by the ratchet lever 35as is the speed of the gear 1.5 which is caused to rotate with theratchet wheel 17 by means of lugs hereinabove mentioned.

When the housing 25 drops down, the lug 37 stops the turning movementthereof about the pivot 27 and with the extended end of the arm 34 aselected distance from the ratchet wheel 1'1 so that the points of thelever 35 will not be. jammed within the cogs of the escapement wheel tofrustrate the escapement operation.

The drum 11 is ordinarily free to rotate. in-

dependently of the shaft 12. When, however, the gear 18 bridges the twogears 14 and 15, the drum 11 will be caused to rotate with the shaft 12.From the foregoing it is deduced that when the lever 21 is rotated bythe weight 40 to release the housing 25, the shaft 12 and the drum 11are caused to rotate by the urge of the spring 13 to unroll thefireproof curtain (not shown) from the drum 11 at a uniform rate ofspeed.

Gears 14 and 15 are mounted in the manner providing for a limitedrotative movement above the members upon which they are carried tofacilitate the common meshing of the gear 18 therewith. To furtherassist the meshing of the teeth upon the gear 18 with those upon thegears 14 and 15, the end of the teeth may be beveled as shown at 14a,15a and 18a, Figure 1.

When it is again desired to set the device for operation, the housing 25may be replaced to the position shown in Figure 1, and the curtainrolled upon the drum 11 by turning the chain gear 30. Thereafter, theshaft 12 is rotated in a counterclockwise direction by inserting aninstrument into the apertures 16 in the gear 15 to obtain leverage forrotating the gear and the shaft 12 against the urge of the spring 13.Each time that the gear 15 is rotated by the instrument, the pawl 32holds the shaft 12 to the mount rotated and against the urge of thespring 13 by engage ing the teeth on the ratchet wheel 1'7. Thus thepawl 32 provides that the shaft 12 may be turned intermittently so thatwhen further turning of the gear 17 by the instrument is prevented bythe instrument striking the wall or the like, the instrument may bewithdrawn and a new engagement had with the gear 15 by means of asucceeding aperture 16.

An alternate, and the preferred method of resetting the device forunrolling the curtain incident to the occurrence of such temperaturewithin the room, is accomplished by using a hook member 50. After thedrum 11 and the spring 13 have been unwound the housing 25 is replacedto the position shown in Figure 1, but the lever 21 is left in theposition as retained by the weight 40, and to hold the compound gear 18in the position to the left, Figure 2, and in mesh with the two gears 14and 15. At this time the gear 28 will be in mesh with the gear 14 sothat when the chain hanging over the gear 30 is operated the gear 14upon turning will turn the gear 15 therewith through the agency of thecompound gear 18. Thus the shaft 12 and the drum 11 are turnedconcurrently against the urging of the spring 13 until the curtain israised. After the curtain is rolled into the elevated position, the hookmember 50 is removed and the arm 25 is held in the horizontal positionby engaging it with the hook 24 at the bottom of the lever2l. Thismethod of re-setting the device turns the shaft 12 and contorts thespring 13 the proper amount for unrolling the curtain upon a futureoccasion.

What is claimed as new and is desired to be secured by Letters Patent ofthe United States is:

1. In combination with a fire door including a drum and a curtain uponsaid drum, a door closing mechanism comprising a shaft coincident withthe axis of said drum and adapted to rotate therein, a spring anchoredindependently of said drum urging said shaft to rotate, a gear upon saiddrum, a gear upon said shaft and juxtaposed to the first named gear, andmeans for connecting said gears to rotate under the urge of said springand at the same speed.

'2. The combination with a fire door including a drum and a curtain uponsaid drum of a door closing mechanism comprising a shaft joumalled insaid drum, a spring anchored independently of said drum urging saidshaft to rotate, a gear upon said shaft to rotate therewith, a gear uponsaid drum in juxtaposition to the first named gear, and a third gear forcoupling the first two gears for rotation under the urge of said springand at the same speed.

3. The combination with a fire door including a drum and a curtain uponsaid drum of a door closing mechanism comprising a rotatable shaftdisposed within said drum coincident with the rotating axis thereof, agear on said shaft to rotate therewith, removable means preventingrotation of said gear and said shaft, a spring urging rotation of saidshaft, a gear on said drum adjacent to the first mentioned gear, amovable support for said means preventing rotation of said shaft, 9.gear movable into common engagement with the first two gears, a leverfor moving said third gear into engagement with said first and secondnamed gears, means on said lever for releasing the movable support andthe means preventing rotation of said shaft concurrently with the movingof said third gear into co-engagement with the first two gears.

4. The combination with a fire door including a drum and a curtain uponsaid drum of a door closing mechanism comprising a rotatable shaft, agear on said shaft for rotating therewith, a spring urging the rotationof said shaft, means for locking said shaft against rotation, a movablebody in support of said locking means and adapted to carry said lockingmeans to an ineffective position when released, an escapement wheelfixed upon said shaft, an escapement lever upon said movable body forengaging said escapement wheel when said body is released, a gear forrotating said drum and positioned next to the first mentioned gear, athird gear adapted to be moved into co-engagement with said first andsecond named gears so that the first named gear may drive the one lastnamed, a lever for moving said third named gear into such co-engagement,and means on said lever for releasing said movable member substantiallyconcurrently with the movement of the third named gear.

5. The combination with a fire-proof door comprising a drum and afireproof curtain upon said drum of an automatic door closing mechanismcomprising a bracket for journalling an end of said drum, a gearconnected to said drum for rotating the drum in said journal, a shaftjournalled in said drum to project therefrom and beyond said bracket, atorsional spring urging said shaft to rotate, a gear attached to saidshaft to rotate therewith and being placed adjacent to the first namedgear, an escapement wheel fixed to said shaft, a body pivotallysupported upon said bracket, means on said pivotal body for locking saidescapement wheel against rotation and being made ineffective incident toa release of said pivotal body, an escapement lever on said pivotal bodyand adapted to engage said escapement wheel incident to the release ofsaid pivotal member, a third gear movable into co-engagement with thefirst and second named gears as a coupling whereby the second named gearmay drive the gear first named, a lever having means for moving thethird gear into said co-engagement and means for releasing said pivotalbody pursuant to a movement thereof, means urging the movement of saidlever and means rendered ineffective at a predetermined ambienttemperature for counteracting the means urging the movement of saidlever.

JOSEPH A. PAUL.

